Mitchell, 35, is a lieutenant on the Madison fire department, where he has served for nearly 15 years. He’s has been active in the effort to recall Republican Gov. Scott Walker and Lt. Gov. Rebecca Kleefisch, speaking across the country against taking away public workers’ collective bargaining rights.

Milwaukee private investigator Ira Robins has also said he plans on running for the Democratic Party’s nomination.

Once election officials determine enough signatures were gathered to trigger a recall, any primary would be May 8 with the general election June 5.